• Beomki Lee, Jae-Hoon Ko, Jin Yang Baek, Haein Kim, Kyungmin Huh, Sun Young Cho, Cheol-In Kang, Doo Ryeon Chung, Kyong Ran Peck, and Eun-Suk Kang.
• Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
• J. Korean Med. Sci. 2023 Sep 18; 38 (37): e292e292.

AbstractAs nucleocapsid protein of severe acute respiratory syndrome coronavirus 2 is immunogenic but not targeted in vaccines, it could be useful in distinguishing natural infection from vaccination. We aimed to investigate the clinical utility of sero-immunological responses against the nucleocapsid protein. Nucleocapsid antibody immunoassay study with 302 coronavirus disease 2019 (COVID-19) patients showed lower titers in immunocompromised patients (P < 0.001), higher titers in higher severity (P = 0.031), and different seroconversion rates and titers according to variants of concern. Longitudinal evaluation of nucleocapsid antibodies using 513 samples from 291 COVID-19 patients revealed that it could persist up to 556 days from symptom onset. Interferon gamma release assay against the nucleocapsid protein showed poor response, precluding the deduction of a cut-off for the nucleocapsid protein. In conclusion, nucleocapsid antibody provides instructive clues about the immunogenicity of nucleocapsid proteins by different seroconversion rates and titers according to the severity of infection, host immune status, and different variants of concern.© 2023 The Korean Academy of Medical Sciences.

12 keywords...

hide…